Transactional Email APIs · reliability comparison
MailerSend vs Mailgun: which is more reliable? (2026)
MailerSend is more reliable than Mailgun, scoring 100.0 vs 83.2 out of 100. Over the last 90 days MailerSend reported 0 incidents and Mailgun reported 10, with effective uptime of 100% and 99.84% respectively.
Data updated Nov 2, 2026 · How we score
| Metric | MailerSend | Mailgun |
|---|---|---|
| Reliability score | 100.0 | 83.2 |
| Rank (transactional email APIs) | — | #7 |
| Uptime (90 days) | 100% | 99.84% |
| Incidents (90 days) | 0 | 10 |
| Partial / major outages | 0 | 3 |
| Avg time to resolve | — | 1h 43m |
| Outages we detected | 0 | 0 |
| Transparency score | 100/100 | 100/100 |
Where MailerSend and Mailgun differ
- MailerSend reported no incidents in the last 90 days, while Mailgun reported 10.
- Mailgun had 3 partial or major outages, compared with 0 for MailerSend.
90-day uptime
MailerSend
Mailgun
- No incidents
- Degraded
- Partial outage
- Major outage
- No data
Recent MailerSend incidents
- MaintenanceSep 23, 2026 · ongoing
Affected: Bulk endpoint, SMTP, Email activity, Delivery time, Email sending API, Email analytics +2 more
- MaintenanceSep 15, 2026 · ongoing
Scheduled maintenance - Email sending affected, 5 min
Affected: Bulk endpoint, SMTP, Delivery time, Email sending API, Inbound routing
Recent Mailgun incidents
- Degraded performanceOct 28, 2026 · resolved in 1h 4m
Affected: Inbound email processing
- Degraded performanceSep 30, 2026 · resolved in 42m
Affected: Inbound email processing
- Degraded performanceSep 14, 2026 · resolved in 58m
Affected: Inbound email processing
- Major outageSep 4, 2026 · resolved in 17m
Affected: API, SMTP, Outbound Delivery, Inbound email processing, Events & Logs, Stats and Analytics
- InformationalSep 4, 2026 · resolved in 34m
- Degraded performanceAug 31, 2026 · resolved in 7h 14m
Affected: Events & Logs
Other transactional email APIs to consider
- Mailjet · #1 · 100% uptime
- Mailtrap Email Sending · #2 · 99.99% uptime
- Loops · #3 · 99.98% uptime
- Twilio SendGrid · #4 · 99.98% uptime
See the full most reliable transactional email apis ranking →